[Chromium] Compositor is applying scroll offset using 'programmatic' API
https://bugs.webkit.org/show_bug.cgi?id=109712

Reviewed by James Robinson.

Ensure that the compositor uses non-programmatic APIs to scroll and
scale.

* src/WebViewImpl.cpp:
(WebKit::WebViewImpl::setPageScaleFactor):
(WebKit::WebViewImpl::updateMainFrameScrollPosition):
(WebKit):
(WebKit::WebViewImpl::applyScrollAndScale):
* src/WebViewImpl.h:
(WebViewImpl):
* tests/WebFrameTest.cpp:
* tests/WebViewTest.cpp:


git-svn-id: http://svn.webkit.org/repository/webkit/trunk@145898 268f45cc-cd09-0410-ab3c-d52691b4dbfc